From: wessels <>
Date: Wed, 24 May 2006 00:24:41 +0000 (+0000)
Subject: Fix NULL pointer access with asyncio when Squid starts up over the disk
X-Git-Tag: SQUID_3_0_PRE4~97
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e65c313fd9eb710ddca93cb5f092299db0edd7eb;p=thirdparty%2Fsquid.git

Fix NULL pointer access with asyncio when Squid starts up over the disk
space limit.

We used to call squidaio_init() from DiskThreadsDiskFile::operator new.
But this only gets called when opening a file.  If the first transaction
is to unlink a file, squidaio will be uninitialized.

I didn't see any other good places to call squidaio_init().  For now
I am calling it from within the squidaio module itself at the
start of each open, unlink/truncate, and stat call.
---

diff --git a/src/DiskIO/DiskThreads/DiskThreadsDiskFile.cc b/src/DiskIO/DiskThreads/DiskThreadsDiskFile.cc
index 8b333f1340..701631f84b 100644
--- a/src/DiskIO/DiskThreads/DiskThreadsDiskFile.cc
+++ b/src/DiskIO/DiskThreads/DiskThreadsDiskFile.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: DiskThreadsDiskFile.cc,v 1.5 2005/04/01 21:11:28 serassio Exp $
+ * $Id: DiskThreadsDiskFile.cc,v 1.6 2006/05/23 18:24:41 wessels Exp $
  *
  * DEBUG: section 79    Disk IO Routines
  * AUTHOR: Robert Collins
@@ -51,7 +51,11 @@ DiskThreadsDiskFile::operator new (size_t)
 {
     CBDATA_INIT_TYPE(DiskThreadsDiskFile);
     DiskThreadsDiskFile *result = cbdataAlloc(DiskThreadsDiskFile);
-    squidaio_init();
+    /*
+     * We used to call squidaio_init() here, but if the first transaction
+     * is to unlink a file (e.g., if Squid starts up over the disk space
+     * limit) then "squidaio" won't be initialized yet.
+     */
 
     return result;
 }
diff --git a/src/DiskIO/DiskThreads/DiskThreadsIOStrategy.cc b/src/DiskIO/DiskThreads/DiskThreadsIOStrategy.cc
index fad9fa5763..3938012f63 100644
--- a/src/DiskIO/DiskThreads/DiskThreadsIOStrategy.cc
+++ b/src/DiskIO/DiskThreads/DiskThreadsIOStrategy.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: DiskThreadsIOStrategy.cc,v 1.4 2005/09/25 21:02:32 hno Exp $
+ * $Id: DiskThreadsIOStrategy.cc,v 1.5 2006/05/23 18:24:41 wessels Exp $
  *
  * DEBUG: section 79    Squid-side Disk I/O functions.
  * AUTHOR: Robert Collins
@@ -56,6 +56,12 @@ DiskThreadsIOStrategy::init(void)
                      aioStats, 0, 1);
 
     initialised = true;
+
+    /*
+     * We'd like to call squidaio_init() here, but the configuration
+     * hasn't been parsed yet and we don't know how many cache_dirs
+     * there are, which means we don't know how many threads to start.
+     */
 }
 
 void
diff --git a/src/DiskIO/DiskThreads/aiops.cc b/src/DiskIO/DiskThreads/aiops.cc
index c8c72f906a..8507de608e 100644
--- a/src/DiskIO/DiskThreads/aiops.cc
+++ b/src/DiskIO/DiskThreads/aiops.cc
@@ -1,5 +1,5 @@
 /*
- * $Id: aiops.cc,v 1.8 2006/05/15 13:39:57 hno Exp $
+ * $Id: aiops.cc,v 1.9 2006/05/23 18:24:41 wessels Exp $
  *
  * DEBUG: section 43    AIOPS
  * AUTHOR: Stewart Forster <slf@connect.com.au>
@@ -685,6 +685,7 @@ squidaio_cancel(squidaio_result_t * resultp)
 int
 squidaio_open(const char *path, int oflag, mode_t mode, squidaio_result_t * resultp)
 {
+    squidaio_init();
     squidaio_request_t *requestp;
 
     requestp = (squidaio_request_t *)squidaio_request_pool->alloc();
@@ -831,6 +832,7 @@ int
 
 squidaio_stat(const char *path, struct stat *sb, squidaio_result_t * resultp)
 {
+    squidaio_init();
     squidaio_request_t *requestp;
 
     requestp = (squidaio_request_t *)squidaio_request_pool->alloc();
@@ -867,6 +869,7 @@ squidaio_do_stat(squidaio_request_t * requestp)
 int
 squidaio_truncate(const char *path, off_t length, squidaio_result_t * resultp)
 {
+    squidaio_init();
     squidaio_request_t *requestp;
 
     requestp = (squidaio_request_t *)squidaio_request_pool->alloc();
@@ -901,6 +904,7 @@ squidaio_do_truncate(squidaio_request_t * requestp)
 int
 squidaio_unlink(const char *path, squidaio_result_t * resultp)
 {
+    squidaio_init();
     squidaio_request_t *requestp;
 
     requestp = (squidaio_request_t *)squidaio_request_pool->alloc();